THEY are four little words that say so much yet cause so much confusion.

No, not “will you marry me?”. That’s another story. This is the story of “It’s in the cloud”.

Cloud computing is something most people do but often with little comprehension of what they are actually doing.

When the US government started to get confused about the term “cloud computing” and what it meant, it ordered the National Institute of Standards and Technology to define it.

It came up with this: “cloud computing can and does mean different things to different people.”

Well, that clears things up then, in a cloudy way.

“Cloud computing” is something we say everyday. A lot.

In fact, there are about 48 million times someone has said it on the web, according to Google. Possibly, quite a number of those occasions were sentences that began with “what the hell is…”, “what the bloody hell is …” and “how do I get a job as the guy at the National Institute of Standards and Technology who has to define …”

The Australian Communications and Media Authority recently released a report into cloud computing in Australia that found that nearly 14 million people in Australia aged 18 years and older had actively used cloud computer services in the past six months. That’s about 80 per cent of the adult population.

For a country famous for its early adoption of technology, that might not seem surprising. Yet it’s a fact that would surprise some of those 14 million people we’re talking about.

The ACMA report found about 55 per cent of the total population had heard of cloud computing, and only 26 per cent of active cloud computer users were aware they had used the cloud.

The MIT Technology Review, which investigated various claims about the origins of the phrase, blames Google — or at least Google CEO Eric Schmidt who said, eight years ago: “It starts with the premise that the data services and architecture should be on servers. We call it cloud computing — they should be in a “cloud” somewhere.”

So, what is cloud computing? PC Mag put it well when it called it “a metaphor for the internet” — although it’s not quite that either.

In simple terms, using cloud computing means storing your files on a place that is not your local hard drive.

Why would you use the cloud? Back in the day, if you were at work and you wanted to use a file that was on your home computer, basically you were buggered.

(Yes, you could ring up your partner and talk them through finding the file or you could connect to your computer using remote connection software — but “you were buggered” is a better general description.)

People got around that by carrying their files on floppy disks. The problem with that is that files got very big and floppy disks were pretty inconvenient (and, also, not always floppy).

That led to other solutions, such as Zip drives (like floppy disks but less convenient) and USB sticks. But still, there are problems with having one version of a file on a portable drive, and potentially different versions of that file on different computers.

By storing that file on a cloud service, such as Google Drive, no matter where you are, you’re always able to access that file (assuming you have access to the internet).

You also don’t have to worry about backups, because the cloud service does the back-up for you.

Cloudy but fine ... Different devices can access files on the same cloud. Picture: Alan OakleySource:News Limited

With people having multiple devices connected to the internet, one of the advantages of using the cloud is that you access the same file across all of your devices.

Let’s say you’re going on a holiday to Paris. Lucky you.

Using a computer, you log onto the website www.tripit.com and put in your flight details. Then when you’re at the airport, you can check the itinerary using your smartphone or tablet.

So, do you use cloud services? Yes, you probably do.

The most common cloud-based system that people use is webmail, such as Gmail.

If you have an iPad or iPhone, then the photos you take are also (assuming you have turned on cloud services) stored on Apple’s cloud which, naturally, is called the iCloud.

If you don’t have an iPad or iPhone and saw Windows 8 as a step forward in operating systems on Windows 7 (really, what were you thinking?), then you might have your files stored on Microsoft OneDrive.

If you use a Kindle, then the book you are reading is stored in the cloud. You’ve put holiday photos on Flickr? That’s the cloud.

Has someone, wanting to send you a large file, emailed you a link from Dropbox? Well, you’ve used cloud computing too.

If you’re still struggling to get your head around the cloud, the thing to know is that it’s not one cloud. It’s a bunch of clouds, and each of those clouds is a different service.

Hard disk woes ... The wheels come off for Jason Segel and Cameron Diaz in Sex Tape when they clash with the cloud. Picture: Claire FolgerSource:AP

Still don’t get the cloud? Here’s a solution — go and have a look at Cameron Diaz in her undies.

In her latest (box-office flopping) movie Sex Tape, Cameron Diaz teams up with Jason Segel as Annie and Jay, a couple who film themselves having sex and then, accidentally, load it up to the cloud so that it’s on a bunch of iPads they gave away.

When Annie expresses some understandable concern that just about everyone they know now has a mobile device containing the sex tape, Jay gives a reasonable defence.

“Nobody understands the cloud,” he yells in response. “It’s a (expletive) mystery.”

Answers to your questions about the cloud

1.Q: If I was to walk to my files stored on the cloud, where would I walk to?

A: Nowhere and everywhere. Cloud companies have “server farms” around the world, and you won’t know where they are and which ones will have your files. But, you know, have a nice walk.

2.Q. Where is the cloud?

We asked Siri, and Google, that very thing. They agree — “a cloud is a visible mass of liquid droplets or frozen crystals”. Silly Siri.

3.Q: It’s all too complicated so why would I want to use it?

A: It’s not complicated and you’re probably using it already.

4.Q: How much is stored in the cloud?

A: According to recent research by Nasuni, there are 1024 Petabytes of data. Or, as some people like to say, 1,0730,741,824 Gb. Or, as we like to say, a really big lot of stuff.

5.Q: Surely it’s all just a fad.

A: Surely you’re joking. And stop calling me …

6. Q. I don’t have a cloud. I think.

A. You could be right. Or, if you have a Gmail account, such as a Gmail email address, then you’re wrong — because that means you have access to storage on your own Google Drive space. Welcome to the cloud brother (or sister).

7. Q. How do I access the cloud?

A. It depends — remember, it’s not one cloud it’s simply a bunch of different services. If it helps, don’t call it THE cloud. Say “how do I store my photos so that I can access them on all Apple devices?” Or call it a wheelbarrow. Wheelbarrows are solid, easy to understand things. It’s just these wheelbarrows are metaphors, which means they’re much easier to move.

8. Q. Shove your wheelbarrow up your metaphor. How do I store my photos so I can access them on all of Apple’s devices?

A. On your iOS device (iPhone or iPad), go to settings, iCloud, Photos then turn on Photo stream. When you take a picture on your iPhone, that photo will appear in My Photo Stream with any iOS device you have that is connected to the same Apple iTunes account. For more help, see http://support.apple.com/kb/HT4486.

9. Q. Do I have an individual cloud or is all my stuff mixed in with everyone else’s?

A. Given the whole “cloud” thing is a metaphor, it depends. Let’s move away from the metaphor to help clear things up. Let’s say you keep documents on Dropbox or Google Drive. Those documents are store on a server (a big hard drive) somewhere — it’s not floating in the air, it’s stored physically on a hard disk somewhere in the world. On this hard disk are other files from other users. So, sure, you’re sharing disk space with users. But it’s not like that means you need to send them a Christmas card. In most cases, your “cloud” is a personal thing — the photos you shoot on your iPhone that are stored in My Photo Stream are just yours. But you can share them with others — if you deliberately do so. Likewise, the files you put in Dropbox or Google Drive, for instance, are yours but you can deliberately share them. Let’s say you and a friend are working on a project you want to keep track of. One of you can create a spreadsheet in Google Docs, and you can make that a shared document with another Google user. That way both of you can have the file open at once and both of you can make changes to it.

10. Q. How do I find out what’s in there?

A. Well, that depends. More specifically, that depends on which cloud service we are talking about. If you have store documents in Dropbox or Google Drive, when you access them online you will log in using a username and password (nope, I can’t help you remember your password) and then you will see your files. If, by the cloud, you mean documents you created in Numbers or Pages of your Apple device, you will find them by opening those applications on your Apple device or by going to www.icloud.com and logging in with your Apple ID.

11. Q. Are there things I have forgot about that are in my cloud that I can’t remember I have — like things stored in the attic?

A. Sure, you look like the forgetful type. Photos are a good example. Let’s say you had a few drinks, released some of those inhabitations of yours and took some photos of a, um, personal nature. You look like that sort too. After a few days, you’ve had a few regrets and deleted them from your iPhone’s camera roll. But they’re also in your Photostream, so your nephew looking at your iPad has probably been checking out your squidgy bits. Also, if you have Dropbox, you might have clicked yes at some stage to the “do you want to automatically back up your photos” prompt. So, that photo you regret is still out there. Really, you need to think about some of your life choices. And, if you’re going to drink to excess, don’t wear those daggy undies.

12. Q. Is there an inventory list?

A. Are you asking is there a place that will tell you everything you have put on every one of the cloud storage services you use, in an easy to read one-stop-shop list. Good question. No there isn’t. But if you create one, let us know. We want to use it too. Until then, you have to remember these are separate services. If it helps, imagine your various cloud accounts as being files stored on different computers on different rooms in your neighbour’s house. You can find files on each but nothing connects all of them (at least not in this analogy — it’s our analogy, come up with your own if you don’t like your neighbours).

13. Q. Can other people see my stuff? If I live in a share house are all my friends on the same cloud?

A. No. Yes. Maybe. You really need to stop thinking of all these cloud services as one happy family. Let’s say you use Gmail, you’ve got photos on Flickr, you have an iPhone and store your photos in My Photos Stream and you sometimes share big files on Dropbox. Your flatmate is in the same situation. But you guys have different accounts, so your files are not in shared drives. He, or she, has his Gmail and Dropbox accounts and you have yours. Of course if you forget to log off a device, or leave a tablet hanging around, then yes they will see your stuff.

14. Q. Will my cloud ever die? A. No company lives forever, so I’m not going to call the files you store on Cloud Service X eternal. But quite possibly you will die first. There’s a not very cheerful thought that might distract you from worrying too much about the cloud.

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